The invention relates to a method and a device for training body parts of a person in a sitting position.
Posture damages are generally diagnosed by a physician and treated with physical therapy by an appropriate practitioner. After a given damage has been diagnosed, it is attempted with rehabilitation measures to stabilize the locomotor system as appropriate. However, attempts already exist to recognize corresponding characteristics by means of automated methods and then eliminate same. This includes, in particular, methods which measure recorded data from movements of the arms, legs or the head. The movement sequences can then be evaluated, after the actual movement activity, by means of various differently implemented analyses.
It is also known, for the operation of computer-aided applications such as a text processing software, to use foot or head operated input devices besides the keyboard and mouse. These attempts are directed towards optional operating options as substitutes for hand-controlled operations.
From DE-OS 39 39 327 a method is known for improving a damaging posture, as well as a measuring device and item of clothing for implementing the inventive method. With these, the body is forced, through an asymmetric load, to take a normal posture. The angle of inclination of lines is measured that connect body parts characteristic for a person""s posture.
From the German utility-model patent 297 12 990 a recognition and warning system for bad sitting postures is known, which issues a warning sound when a user""s head moves too closely to a surface. This is done by evaluating the amount of coverage of a light sensor by the head.
The German utility model 296 12 724 describes a device for computer-aided balance therapy with a ball section, which has an enlarged cut surface as a standing platform for persons. A control of a computer program takes place by means of built-in switches. The ball section is anchored centrally inside a switch holder ring so that it is movable in all lateral directions. The switches that are located in the switch holder ring can be actuated by shifts in the person""s balance. The switching operation causes a monitor cursor to be moved in corresponding directions.
DE-OS 40 21 240 describes a device for checking the posture of persons during their use of training equipment, seats or the like. The device comprises at least one pressure sensitive sensor element, a carrying element for the sensor element or elements and an evaluation unit. The carrying element can be attached to the respective training equipment, seat or the like in such a manner that the person, in dependence on the person""s posture, exerts a certain pressure on the sensor element or elements. The output signals of the sensor elements are applied to the evaluation unit. The evaluation unit comprises a display unit, which shows the posture currently taken by the person.
A device for the functional and quantified evaluation of the human activity is described in the U.S. Pat. No. 5,375,610. The device comprises four main components: a data acquisition unit, a body suit interface, a body suit with a multitude of switches and a graphically oriented software package. The switches are arranged on the body suit in such a manner that they can acquire the movements that are to be measured. Graphical analysis means can be connected to the sensors via data acquisition means. The graphical analysis means provide, by means of match stick men, a visual presentation of body and arm positions across time in real time. This may be used as movement feedback. The various postures can, furthermore, be illustrated on the monitor with the aid of match stick men. For this purpose the user selects the posture to be shown from a list.
In the state of the art described below, the efforts are targeted at optimized operating means for a computer that are equivalent to hand-operated controls.
In WO96/01448 a control device for computers or industrial processes is described. The concept is based on the principle of controlling a computer through movements of the body, which are transmitted via the chair. The control device is characterized in that a plurality of transducers are built into a chair. A first transducer is provided to detect turning movements of the chair. It transmits signals that correspond to movements in the horizontal direction. A further transducer detects movements in the vertical direction. The output signals of the transducers are routed to a transmitter via an interface. In this manner a conventional mouse can be completely or partly replaced by movements of the chair. Turning movements, for example, activate a cursor on a display unit in the horizontal direction, whereas back and forth movements of the body move the cursor in the vertical direction.
In the German utility model 297 04 478 a device is described for the operation of a joystick by a standing or sitting operator. A horizontally arranged plate is mounted above a joystick that is to be operated so that the plate is tiltable and movable. On its underside, an operating mechanism is provided for the lateral movement of the joystick, which operates the joystick when the plate is tilted. An operator stands or sits on this plate and shifts his body weight, which results in a tilting of the plate, thus in the operation of the joystick and thus, in turn, in the desired interaction with a game or a virtual world.
In the U.S. Pat. No. 4,843,538 a device and process are described by which a real time control of computer events can be performed via an image of a human body. This is done with a perception and characteristics analysis.
The invention is now based on the object of presenting a method and a device for training body parts of a person in a sitting position whereby body movements can be detected and controlled.
The first object is met, with respect to the method, with the following procedure steps:
specification of a desired movement,
generation of movement signals from a movement of a sitting person by means of a sensor unit, and
generation of a presentation of the movement from the movement signals on a monitor.
This permits the display, monitoring and correction of body movements and postures, particularly also bad postures. The sensory monitoring and the display permit a qualified guiding of movements. For example, a special movement program may be specified that has been developed by a physician for a certain problem, for rehabilitation purposes. The monitoring of the movement program is carried out automatically via the sensor technology without a need for a long-lasting presence of a trained practitioner.
A further advantage of the invention lies in the fact that known problems in the posture and locomotor system in the continuously expanding area of personal computer jobs can be improved by means of the additive or also optional use of the invention. The user may be prompted, either permanently or for limited periods of time, for example by means of a back relaxation software, to use the movement-activating input system. This option would prophylactically counteract the loss of mobility and the curvatures of the spine seen in this line of work.
Furthermore, the possibility exists to set up virtual rehabilitation worlds, in which, e.g., a physician or therapist specifies a movement to a therapy group. The protocol of the movement can additionally be transmitted to the physician or therapist. For control purposes the participants in the therapy group can monitor the presentation of the movement on a monitor, like in a mirror.
An advantageous embodiment is characterized in that the desired movement is specified in the form of a desired path, which a cursor is to follow on the monitor. Specifying a desired path permits a targeted therapeutic guidance of movements.
In a further advantageous embodiment of the invention, the movement of the person is transmitted to the sensor unit via a seat device. In this manner various seat devices may be used that have been developed under therapeutic aspects.
A further advantageous embodiment is characterized in that a quality signal is formed from the desired movement and the movement signals, as a measure for the correspondence between the desired movement and the movement. The quality signal provides the patient with feedback on the overall success of the therapeutic movements that were just performed. A therapeutic quality measure is thus introduced, which may serve for the comparability of different persons or also for different training units for one person.
The movement signals are preferably detected and presented quasi-continually. Quasi-continually, in this context, means that, with digital signal processing, the scanning rate for a conversion of the* into a digital format of the movement signals, which are generally initially present in analog form, is so high that an observer gains the impression of a continuous acquisition and presentation.
*Translator""s note: this is a literal translation of the respective part of the German sentence, which is either incomplete or contains an extraneous xe2x80x9cof thexe2x80x9d (German xe2x80x9cderxe2x80x9d). 
The second object, with respect to the device, is met with the combination of the following characteristics
means for specifying a desired movement,
a sensor arrangement for generating movement signals from a movement of a sitting person,
a processing unit that is connected to the sensor arrangement for generating a presentation of the movement from the movement signals, and
a monitor that is connected to the processing unit for a visualization of the presentation.
The resolution of the sensor elements corresponds to the resolution of a monitor of e.g., approximately 1200xc3x97800 pixels. The movement signals may be routed to the processing unit after they have been processed in an analog or also digital form.
An advantageous embodiment is characterized in that a seat device is connected to the sensor arrangement for transmitting forces to the sensor arrangement that are generated by the movement of the sitting person. This permits a normal basic posture to be taken during its use.
The seat device may be designed as a chair or stool. In a particularly advantageous design a ball seat is used as the seat device. Ball seats are medically recognized for the therapy of posture damages, and furthermore convert the body movement into easily detected rolling motions.
In a further advantageous design the sensor arrangement comprises a multitude of sensor elements arranged on a surface. With these, the movement of a ball seat lying on same can be measured by the shifting of the imprint of the ball seat on the sensor arrangement. The sensor elements detect the movement, for instance by pressure sensitivity, distance sensitivity or path sensitivity, rotation sensitivity, speed sensitivity or acceleration sensitivity. The sensor arrangement may be designed, e.g., as an appropriately sensitive mat. The sensor principles may be electrical, magnetic, optical or also mechanical receptors, such as light barriers, piezo sensors, Hall sensors, etc. Further designs of the invention are characterized by the subclaims.